DOCSLIB.ORG

The Effect of Ram Pressure on the Molecular

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Effect of Ram Pressure on the Molecular The effect of ram pressure on the molecular gasof galaxies: three case studies in the Virgo cluster: three case studies in the Virgo cluster Bumhyun Lee, Aeree Chung, Stephanie Tonnesen, Jeffrey Kenney, O. Ivy Wong, B. Vollmer, Glen Petitpas, Hugh Crowl, Jacqueline van Gorkom To cite this version: Bumhyun Lee, Aeree Chung, Stephanie Tonnesen, Jeffrey Kenney, O. Ivy Wong, et al.. The effectof ram pressure on the molecular gas of galaxies: three case studies in the Virgo cluster: three case studies in the Virgo cluster. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2017, 466 (2), pp.1382-1398. 10.1093/mnras/stw3162. hal-03161862 HAL Id: hal-03161862 https://hal.archives-ouvertes.fr/hal-03161862 Submitted on 17 Mar 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. MNRAS 466, 1382–1398 (2017) doi:10.1093/mnras/stw3162 Advance Access publication 2016 December 7 The effect of ram pressure on the molecular gas of galaxies: three case studies in the Virgo cluster Bumhyun Lee,1‹ Aeree Chung,1,2,3‹ Stephanie Tonnesen,4 Jeffrey D. P. Kenney,5 O. Ivy Wong,6 B. Vollmer,7 Glen R. Petitpas,8 Hugh H. Crowl9 and Jacqueline van Gorkom10 1Department of Astronomy, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea 2Yonsei University Observatory, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea 3 Joint ALMA Observatory, Alonso de Cordova´ 3107 Vitacura, Santiago, Chile Downloaded from https://academic.oup.com/mnras/article/466/2/1382/2646788 by guest on 17 March 2021 4Carnegie Observatories, 813 Santa Barbara St, Pasadena, CA 91101, USA 5Yale University Astronomy Department, PO Box 208101, New Haven, CT 06520-8101, USA 6International Centre for Radio Astronomy Research, The University of Western Australia M468, 35 Stirling Highway, Crawley, WA 6009, Australia 7CDS, Observatoire astronomique de Strasbourg, Universite´ de Strasbourg, CNRS, UMR 7550, 11 rue de l’Universite,´ F-67000 Strasbourg, France 8Harvard–Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 9Division of Science and Mathematics, Bennington College, 1 College Drive, Bennington, VT 05201, USA 10Department of Astronomy, Columbia University, Mail Code 5246, 550 W 120th St, New York, NY 10027, USA Accepted 2016 December 2. Received 2016 December 2; in original form 2016 July 16 ABSTRACT We present 12CO (2–1) data of three Virgo spirals – NGC 4330, NGC 4402 and NGC 4522 obtained using the Submillimeter Array. These three galaxies show clear evidence of ram pressure stripping due to the cluster medium as found in previous H I imaging studies. Using the high-resolution CO data, we investigate how the properties of the inner molecular gas disc change while a galaxy is undergoing H I stripping in the cluster. At given sensitivity limits, we do not find any clear signs of molecular gas stripping. However, both its morphology and kinematics appear to be quite disturbed as those of H I. Morphological peculiarities present in the molecular and atomic gas are closely related with each other, suggesting that the molecular gas can be also affected by strong intracluster medium (ICM) pressure even if it is not stripped. CO is found to be modestly enhanced along the upstream sides in these galaxies, which may change the local star formation activity in the disc. Indeed, the distribution of Hα emission, a tracer of recent star formation, well coincides with that of the molecular gas, revealing enhancements near the local CO peak or along the CO compression. FUV and Hα share some properties in common, but FUV is always more extended than CO/Hα in the three galaxies, implying that the star-forming disc is rapidly shrinking as the molecular gas properties have changed. We discuss how ICM pressure affects dense molecular gas and hence star formation properties while diffuse atomic gas is being removed from a galaxy. Key words: ISM: molecules – galaxies: clusters: intracluster medium – galaxies: evolution – galaxies: ISM – galaxies: spiral. deficient in H I compared to field galaxies based on their single- 1 INTRODUCTION dish observations. In addition, Giovanelli & Haynes (1985)have Since Gunn & Gott (1972) suggested that a galaxy might lose found that the H I content is well correlated with the location of its interstellar medium (ISM) by interacting with the intracluster galaxies in a sense that H I is more deficient at smaller distances medium (ICM) in the cluster environment, much evidence for ram from the cluster centre. Then the H I synthesis imaging studies such pressure stripping has been found to date. In early days, Davies & as Warmels (1988a,b) and Cayatte et al. (1990) have shown that H I- Lewis (1973) have shown that Virgo galaxies are generally more deficient galaxies near the cluster centre have small H I-to-optical extents, truncated within the stellar disc in many cases. In a more recent high-resolution H I imaging study of ∼50 selected Virgo E-mail: [email protected] (BL); [email protected] (AC) galaxies by Chung et al. (2009), a number of galaxies have been C 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society Molecular gas properties of Virgo spirals 1383 found with various scales of extraplanar H I gas or long H I tails, Therefore, in order to get a deeper understanding on how galax- indicating that ram pressure stripping is indeed acting in the cluster ies become passive after H I stripping, not only the possibility of environment. stripping but also the detailed properties of molecular gas inside a As a galaxy loses its ISM, the star formation rate is expected to galaxy under strong ICM pressure need to be probed. Hence, using be suppressed, which agrees well with the observations. As a good the Submillimeter Array (SMA),1 we have taken high-resolution example, Koopmann & Kenney (2004a) find that the massive star 12CO (2–1) imaging data of a subsample of Virgo galaxies that formation rate of Virgo spirals is lower than their field counterpart have lost atomic gas significantly by ICM pressure. Some prelim- by a factor of 2.5 on average. Koopmann & Kenney (2004b) also inary results are published in Lee & Chung (2015),andinthis show that many Virgo spirals have a smaller Hα extent compared work, we present more complete analysis on both morphology and to their stellar disc, reflecting that the process truncating H I discs kinematics of three Virgo galaxies based on the SMA data. may also be acting on the star-forming disc and Hα emission. This paper is organized as follows. We introduce the sample in On the other hand, molecular gas is unlikely to be as easily Section 2. Details of observations and data reduction procedure stripped as atomic hydrogen, since it is more tightly bound to the are provided in Section 3. In Section 4, we present the SMA data, galactic centre and the density is higher. In fact, most previous stud- describing the CO morphology and kinematics. In Section 5, we Downloaded from https://academic.oup.com/mnras/article/466/2/1382/2646788 by guest on 17 March 2021 ies find that the molecular gas mass of the cluster population is not compare the CO and other wavelength data to discuss how the significantly different from that of field galaxies (Stark et al. 1986; molecular gas in these galaxies has been affected by the ICM pres- Kenney & Young 1989). In addition, more recent studies are finding sure. In Section 6, we summarize the results and conclude. clumpy dust features in the upstream side of H I gas stripped galax- A distance of 16 Mpc (1 arcsec ∼78 pc) to Virgo cluster is adopted ies, which are likely to be surviving dense clouds that are unveiled in this work (Yasuda, Fukugita & Okamura 1997). after diffuse atomic gas is removed (Crowl et al. 2005;Abramson & Kenney 2014; Kenney, Abramson & Bravo-Alfaro 2015). On the other hand, however, the opposite results have also been 2 SAMPLE GALAXIES reported. Rengarajan & Iyengar (1992) find that H2 mass normalized The sample for the SMA observations has been selected from by the dynamical mass of galaxies tends to get larger with increasing the VLA (Very Large Array)2 Imaging study of Virgo galaxies clustercentric distance, which supports that the molecular gas can be in Atomic gas (VIVA) by Chung et al. (2009). The VIVA is a high- also deficient in the cluster environment. More recently, Boselli et al. resolution H I imaging study of 53 late-type galaxies that are located (2014) show that H I-deficient galaxies in the cluster environment throughout the Virgo cluster from a high-density core region to low- tend to be also modestly deficient in molecular gas. density outskirts. Among the VIVA sample, we have selected three However, the molecular gas fraction to the optical luminosity of galaxies with clear evidence for active H I stripping, NGC 4330, spiral galaxies measured using 12CO (1–0) ranges quite widely for NGC 4402 and NGC 4522 (Fig. 1). Although these galaxies are all environments (Chung 2012). This implies that the molecular gas thought to have lost a similar fraction of H I gas, being deficient by fraction alone may not be a good tracer of molecular gas deficiency.
Load more

Recommended publications
  • Ram Pressure Stripping and Galaxy Orbits: the Case of the Virgo Cluster
    Ram pressure stripping and galaxy orbits: The case of the Virgo cluster B. Vollmer Max-Planck-Institut f¨ur Radioastronomie, Bonn, Germany and Observatoire de Paris, Meudon, France. V. Cayatte, C. Balkowski Observatoire de Paris, DAEC, UMR 8631, CNRS et Universit´e Paris 7, F-92195 Meudon Cedex, France. and W.J. Duschl1 Institut f¨ur Theoretische Astrophysik der Universit¨at Heidelberg, Tiergartenstraße 15, D-69121 Heidelberg, Germany. ABSTRACT We investigate the role of ram pressure stripping in the Virgo cluster using N-body simulations. Radial orbits within the Virgo cluster’s gravitational potential are modeled and analyzed with respect to ram pressure stripping. The N-body model consists of 10 000 gas cloud complexes which can have inelastic collisions. Ram pressure is modeled as an additional acceleration on the clouds located at the surface of the gas distribution in the direction of the galaxy’s motion within the cluster. We made several simulations changing the orbital parameters in order to recover different stripping scenarios using realistic temporal ram pressure profiles. We investigate systematically the influence of the inclination angle between the disk and the orbital plane of the galaxy on the gas dynamics. We show that ram pressure can lead to a temporary increase of the central gas surface density. In some cases a considerable part of the total atomic gas mass (several 108 M ) can fall back onto the galactic disk after the stripping event. A quantitative relation between the orbit parameters and the resulting Hi deficiency is derived containing explicitly the inclination angle between the disk and the orbital plane.
    [Show full text]
  • Ram Pressure Stripping of the Multiphase ISM and Star Formation in the Virgo Spiral Galaxy NGC 4330
    A&A 537, A143 (2012) Astronomy DOI: 10.1051/0004-6361/201117680 & c ESO 2012 Astrophysics Ram pressure stripping of the multiphase ISM and star formation in the Virgo spiral galaxy NGC 4330 B. Vollmer1,M.Soida2, J. Braine3,A.Abramson4, R. Beck5, A. Chung6,H.H.Crowl7, J. D. P. Kenney4, and J. H. van Gorkom7 1 CDS, Observatoire astronomique de Strasbourg, UMR 7550, 11 rue de l’université, 67000 Strasbourg, France e-mail: [email protected] 2 Astronomical Observatory, Jagiellonian University, Kraków, Poland 3 Laboratoire d’Astrophysique de Bordeaux, Université de Bordeaux, OASU, CNRS/INSU, 33271 Floirac, France 4 Yale University Astronomy Department, PO Box 208101, New Haven, CT 06520-8101, USA 5 Max-Planck-Insitut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany 6 Department of Astronomy and Space Science, Yonsei University, Republic of Korea 7 Department of Astronomy, Columbia University, 538 West 120th Street, New York, NY 10027, USA Received 11 July 2011 / Accepted 11 November 2011 ABSTRACT It has been shown that the Virgo spiral galaxy NGC 4330 shows signs of ongoing ram pressure stripping at multiple wavelengths. At the leading edge of the interaction, the Hα and dust extinction curve sharply out of the disk. On the trailing side, a long Hα/UV tail has been found which is located upwind of a long Hi tail. We complement the multiwavelength study with IRAM 30m HERA CO(2–1) and VLA 6 cm radio continuum observations of NGC 4330. The data are interpreted with the help of a dynamical model including ram pressure and, for the first time, star formation.
    [Show full text]
  • Small Near-Earth Asteroids As a Source of Meteorites
    Small Near-Earth Asteroids as a Source of Meteorites Jiří Borovička and Pavel Spurný Astronomical Institute of the Czech Academy of Sciences Peter Brown University of Western Ontario __________________________________________________________________________ Small asteroids intersecting Earth’s orbit can deliver extraterrestrial rocks to the Earth, called meteorites. This process is accompanied by a luminous phenomena in the atmosphere, called bolides or fireballs. Observations of bolides provide pre-atmospheric orbits of meteorites, physical and chemical properties of small asteroids, and the flux (i.e. frequency of impacts) of bodies at the Earth in the centimeter to decameter size range. In this chapter we explain the processes occurring during the penetration of cosmic bodies through the atmosphere and review the methods of bolide observations. We compile available data on the fireballs associated with 22 instrumentally observed meteorite falls. Among them are the heterogeneous falls Almahata Sitta (2008 TC3) and Benešov, which revolutionized our view on the structure and composition of small asteroids, the Příbram-Neuschwanstein orbital pair, carbonaceous chondrite meteorites with orbits on the asteroid-comet boundary, and the Chelyabinsk fall, which produced a damaging blast wave. While most meteoroids disrupt into fragments during atmospheric flight, the Carancas meteoroid remained nearly intact and caused a crater-forming explosion on the ground. 1. INTRODUCTION Well before the first asteroid was discovered, people unknowingly had asteroid samples in their hands. Could stones fall from the sky? For many centuries, the official answer was: NO. Only at the end of the 18th century and the beginning of the 19th century did the evidence that rocks did fall from the sky become so overwhelming that this fact was accepted by the scientific community.
    [Show full text]
  • Dynamics of the Polonnaruwa Meteorite Fall
    EPSC Abstracts Vol. 8, EPSC2013-803, 2013 European Planetary Science Congress 2013 EEuropeaPn PlanetarSy Science CCongress c Author(s) 2013 Dynamics of the Polonnaruwa meteorite fall S. G. Coulson (1), M. K. Wallis (1), N. Miyake (1), J. Wallis (2), N. C. Wickramasinghe (1) (1) Buckingham Centre for Astrobiology, The University of Buckingham, Buckingham MK18 1EG, UK (2) School of Mathematics, Cardiff University, Cardiff,UK ([email protected] ) Abstract 1. Introduction The Polonnaruwa meteorite fell over the north east of Disintegration of meteoroids descending through the Sri Lanka on 29 Dec. 2012, with the fireball observed atmosphere is usually described by a process of descending at 18.30 local time. Fragments were continual ablation where the energy absorbed in picked up the following day from paddy fields, sized heating the bolide is proportional to the cube of its 3 from 10-15cm down to few mm. Meteorite speed (u ) [1] or by catastrophic fragmentation when fragments were readily identifiable on top of the the ram pressure (µ u2) exceeds the tensile strength sandy soil and scattered over an area of 1 km scale. of the body [2]. Both these models predict that ~ 1m The meteorites are unusually fragile and porous, with radii, low density meteoroids such reach a minimum mean density less than water. A thin fusion crust is altitude of 30-20 km. From analysis of a Leonid found around some cm-sized pieces. From their meteoroid, Coulson [3] suggested that ~90% of the spatial distribution, we infer the meteoroid survived initial mass of cometary fragments are a composite of to an unusually low altitude ~10km.
    [Show full text]
  • Modelling of Bingham and Herschel-Bulkley Flows with Mixed
    Journal of Non-Newtonian Fluid Mechanics 228 (2016) 1–16 Contents lists available at ScienceDirect Journal of Non-Newtonian Fluid Mechanics journal homepage: www.elsevier.com/locate/jnnfm Modelling of Bingham and Herschel–Bulkley flows with mixed P1/P1 finite elements stabilized with orthogonal subgrid scale Elvira Moreno a, Antonia Larese b,∗, Miguel Cervera b a Departamento de Ordenación de Cuencas, Ingeniería Forestal, Universidad de los Andes, ULA, Vía Chorros de Milla, 5101, Mérida Venezuela b International Center for Numerical Methods in Engineering (CIMNE), Technical University of Catalonia (UPC), Edificio C1, Campus Norte, Jordi Girona1-3, 08034, Barcelona Spain article info abstract Article history: This paper presents the application of a stabilized mixed pressure/velocity finite element formulation to Received 3 August 2015 the solution of viscoplastic non-Newtonian flows. Both Bingham and Herschel–Bulkley models are con- Revised 27 November 2015 sidered. Accepted 12 December 2015 Available online 19 December 2015 The detail of the discretization procedure is presented and the Orthogonal Subgrid Scale (OSS) stabiliza- tion technique is introduced to allow for the use of equal order interpolations in a consistent way. The Keywords: matrix form of the problem is given. Bingham flows Herschel–Bulkley flows A series of examples is presented to assess the accuracy of the method by comparison with the results Variational multiscale stabilization obtained by other authors. The extrusion in a Bingham fluid and the movement of a moving and rotating Orthogonal subscale stabilization cylinder are analyzed in detail. The evolution of the streamlines, the yielded and unyielded regions, the Moving cylinder drag and lift forces are presented.
    [Show full text]
  • Dust Streamers in the Virgo Galaxy M86 from Ram Pressure Stripping
    Astronomical Journal, August 2000, in press Dust Streamers in the Virgo Galaxy M86 from Ram Pressure Stripping of its Companion VCC 882 Debra Meloy Elmegreen1, Bruce G. Elmegreen2, Frederick R. Chromey1, Michael S. Fine1,3 ABSTRACT The giant elliptical galaxy M86 in Virgo has a ∼ 28 kpc long dust trail inside its optical halo that points toward the nucleated dwarf elliptical galaxy, VCC 882. The trail seems to be stripped material from the dwarf. Extinction measurements suggest that the ratio of the total gas mass in the trail to the blue luminosity of the dwarf is about unity, which is comparable to such ratios in dwarf irregular galaxies. The ram pressure experienced by the dwarf galaxy in the hot gaseous halo of M86 was comparable to the internal gravitational binding energy density of the presumed former gas disk in VCC 882. Published numerical models of this case are consistent with the overall trail-like morphology observed here. Three concentrations in the trail may be evidence for the predicted periodicity of the mass loss. The evaporation time of the trail is comparable to the trail age obtained from the relative speed of the galaxies and the trail length. Thus the trail could be continuously formed from stripped replenished gas if the VCC 882 orbit is bound. However, the high gas mass and the low expected replenishment rate suggest that this is only the first stripping event. Implications for the origin of nucleated dwarf ellipticals arXiv:astro-ph/0005243v1 11 May 2000 are briefly discussed. Subject headings: galaxies: interactions — galaxies: individual (M86) — galaxies: kinematics and dynamics — galaxies: clusters 1Department of Physics and Astronomy, Vassar College, Poughkeepsie, NY 12604; e–mail: [email protected], [email protected] 2IBM Research Division, T.J.
    [Show full text]
  • Commencement Program
    Graduate School of Arts and Sciences Commencement Ceremony Yale University Sunday, May 23, 2021 Order of Exercises commencement ceremony Graduate School of Arts and Sciences Sunday, May 23, 2021 Academic Procession Peter Salovey Michelle Nearon University President Senior Associate Dean for Graduate Student Chris Argyris Professor of Psychology Development and Diversity Lynn Cooley Allegra di Bonaventura Dean, Graduate School of Arts and Sciences Associate Dean for Graduate Student Academic Vice Provost for Postdoctoral Afairs Support C.N.H Long Professor of Genetics, Professor of Cell Ann Gaylin Biology and Molecular, Cellular and Developmental Associate Dean for Graduate Education Biology Lisa Brandes Akiko Iwasaki Assistant Dean for Student Life Waldemar Von Zedtwitz Professor of Immunobiology and Molecular, Cellular and Developmental Biology, Danica Tisdale Fisher and Professor of Epidemiology Assistant Dean of Diversity Gary Brudvig Lucylle Armentano ’21 PhD in Psychology Benjamin Silliman Professor of Chemistry Student Marshal Kelly Shue Stephen Gaughran ’21 PhD in Ecology and Professor of Finance Evolutionary Biology Student Marshal Sharon Kugler University Chaplain Pamela Schirmeister Deputy Dean and Dean of Strategic Initiatives commencement ceremony Graduate School of Arts and Sciences Sunday, May 23, 2021 Greetings Lynn Cooley Dean, Graduate School of Arts and Sciences Vice Provost for Postdoctoral Afairs C.N.H Long Professor of Genetics, Professor of Cell Biology and Molecular, Cellular and Developmental Biology President’s
    [Show full text]
  • (Ram) Pressure
    news & views GALAXY CLUSTERS Under (ram) pressure Galaxy clusters are considered to be galactic incubators that accelerate the evolution of galaxies within them. One of the effects that might induce such an accelerated evolution is ram-pressure stripping. A galaxy falling into a cluster’s gravitational potential feels pressure due to interaction with the intracluster medium. This ram pressure can lead to gas from the infalling galaxy being stripped, potentially leading to depletion of its gas reservoirs and hence limiting its capacity to form stars. William Cramer and collaborators used very sensitive Hubble Space Telescope (HST) observations to constrain the gas and star formation properties of such a galaxy undergoing ram-pressure stripping within the Coma cluster (preprint at https://arxiv.org/abs/1811.04916; 2018). The Coma cluster contains more than a thousand confirmed galaxy members and is at a distance of roughly 0.1 Gpc from Earth. D100 is a spiral galaxy at approximately 240 kpc from the cluster centre that shows a 60-kpc-long and 1.5-kpc-wide tail (long bright-red plume, pictured) that was originally observed in ionized Hα emission. The new HST observations in the ultraviolet and optical allowed the Credit: STScI/J. DePasquale identification of star-forming regions within the tail, as well as the mapping of its dust content and structure. The authors The authors also looked at star potentially, young stars. While their origin identified young (< 100 Myr) stellar formation in the main body of the galaxy remains unclear, a potential scenario complexes within the tail and concluded D100 itself.
    [Show full text]
  • The Combined Effects of Ram Pressure Stripping, and Tidal Influences On
    ThThee CombinCombineded effeffectectss ooff rraamm pprreessussurree ststrrippippining,g, aandnd tidatidall ininflufluencenceses onon VVirgoirgo cluclustesterr ddwwaarrff ggalaxalaxieies,s, uusinsingg N-boN-body/dy/ SSPHPH ssimimuulatlationion Author: Rory Smith, Cardiff University Collaborators: Jonathon Davies, Cardiff University Alistair Nelson , Cardiff University The importance of dwarf galaxies ● Dwarf galaxy ± low mass & luminosity (-18<Mabs<-14) ● Building blocks of other galaxies ● Small potential wells ± strongly effected by environment. SDSS RGB , VCC009 The Cluster Environment Ram Pressure stripping: Harassment: Moore et al,1999 Virgo in X-rays, ROSAT satellite CGCG 97079 ± Radio continuum & Halpha, Moore et al,1999 Boselli & Gavazzi 2006 The Morphology-density relation in dwarfs dwarf irregulars (star-forming, gas-rich, blue) preferentially found in the field, dwarf ellipticals (old stars, no gas, red and dead) found preferentially in clusters How did dwarf ellipticals (dEs) form? Observations of cluster dEs show signatures of recent infall (e.g. Conselice et al, 2001) Possible origins: ● Harassed medium-mass low surface brightness spirals? (Moore et al, 1999) ● Ram Pressure Stripped in-falling dwarf irregular galaxies? (Boselli et al, 2008) => likely both mechanisms occurring simultaneously within cluster, so.... Simulations combining both mechanisms for the first time, investigating their separate and combined influence on in-falling dwarf galaxies Model dwarf irregular galaxies: Dark matter halo Stellar disk Gas disk X-Y
    [Show full text]
  • An Orbital Study of Intense Ram-Pressure Stripping in Clusters
    Mon. Not. R. Astron. Soc. 000, 000{000 (0000) Printed 28 February 2018 (MN LATEX style file v2.2) GASP IX. Jellyfish galaxies in phase-space: an orbital study of intense ram-pressure stripping in clusters Yara L. Jaff´e1?, Bianca M. Poggianti2, Alessia Moretti2, Marco Gullieuszik2, Rory Smith3, Benedetta Vulcani4;2, Giovanni Fasano2, Jacopo Fritz5, Stephanie Tonnesen6, Daniela Bettoni2, George Hau1, Andrea Biviano7, Callum Bellhouse8, Sean McGee8 1European Southern Observatory, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago de Chile, Chile 2INAF - Osservatorio Astronomico di Brera, via Brera 28, 20122 Milano, Italy 3 Korea Astronomy and Space Science Institute, 766, Daedeokdae-ro, Yuseon-gu, Daejon, 34055, Korea 4 School of Physics, The University of Melbourne, VIC 3010, Australia. 5 Instituto de Radioastronoma y Astrof´ısica, Morelia, Mexico 6 Center for Computational Astrophysics, Flatiron Institute, 162 5th Ave, New York, NY 10010, USA 7 INAF - Astronomical Observatory of Trieste, 34143 Trieste, Italy 8 University of Birmingham School of Physics and Astronomy, Edgbaston, Birmingham, England 28 February 2018 ABSTRACT It is well known that galaxies falling into clusters can experience gas stripping due to ram-pressure by the intra-cluster medium (ICM). The most spectacular examples are galaxies with extended tails of optically-bright stripped material known as “jellyfish”. We use the first large homogeneous compilation of jellyfish galaxies in clusters from the WINGS and OmegaWINGS surveys, and follow-up MUSE observations from the GASP MUSE programme to investigate the orbital histories of jellyfish galaxies in clusters and reconstruct their stripping history through position vs. velocity phase- space diagrams. We construct analytic models to define the regions in phase-space where ram-pressure stripping is at play.
    [Show full text]
  • AST242 LECTURE NOTES PART 1 Contents 1. Introduction to Ideal
    AST242 LECTURE NOTES PART 1 Contents 1. Introduction to Ideal Fluid Dynamics 2 1.1. Variables 2 1.2. Eulerian and Lagrangian views 2 1.3. Streamlines and Flow visualization 3 1.4. Conservation of Mass 5 1.5. Conservation of momentum 7 1.6. Hydrostatic equilibrium 8 1.7. When is hydrostatic equilibrium a good approximation? 9 1.8. Failure of continuum fluid approximation 9 1.9. Isopotential and isodensity contours 11 1.10. Isothermal atmosphere with constant g 11 1.11. One dimensional examples 12 1.12. Source terms 14 1.13. Stress tensor 15 1.14. What is a tensor? 18 2. Conservation of Energy 20 2.1. Heat Flux, Adiabatically 20 2.2. Heat flux with conductivity and heating or cooling 22 2.3. Pressure with a radiation field 23 2.4. Conservation of Energy 25 2.5. A polytropic gas and equations of state 26 2.6. The Lame-Enden equation 27 3. Microphysical Basis for Continuum Equations 28 3.1. The particle distribution function 28 3.2. Boltzmann equation 30 3.3. Conservation of mass 31 3.4. Conservation of momentum 32 3.5. Validity of continuum fluid approximation 33 4. Summation notation, the permutation tensor and some index gymnastics 34 5. Extremely Short Introduction to Relativistic Hydrodynamics 35 6. Acknowledgements 38 1 2 AST242 LECTURE NOTES PART 1 1. Introduction to Ideal Fluid Dynamics 1.1. Variables. A fluid is characterized by a mean velocity field u(x; t) and at least two integrated or thermodynamic quantities. Often these are the mass density, ρ(x; t) and pressure p(x; t).
    [Show full text]
  • Ram Pressure and Dusty Red Galaxies – Key Factors in the Evolution of the Multiple Cluster System Abell 901/902
    A&A 549, A142 (2013) Astronomy DOI: 10.1051/0004-6361/201219244 & c ESO 2013 Astrophysics Ram pressure and dusty red galaxies – key factors in the evolution of the multiple cluster system Abell 901/902 B. Bösch1, A. Böhm1,C.Wolf2, A. Aragón-Salamanca3,M.Barden1,M.E.Gray3,B.L.Ziegler4, S. Schindler1, and M. Balogh5 1 Institute for Astro- and Particle Physics, University of Innsbruck, Technikerstr. 25/8, 6020 Innsbruck, Austria e-mail: [email protected] 2 Department of Physics, Denys Wilkinson Building, University of Oxford, Keble Road, Oxford OX1 3RH, UK 3 School of Physics and Astronomy, The University of Nottingham, University Park, Nottingham NG7 2RD, UK 4 Department of Astronomy, University of Vienna, Türkenschanzstr. 17, 1180 Wien, Austria 5 Department of Physics, University of Waterloo, Waterloo, ON N2L 3G1, Canada Received 19 March 2012 / Accepted 16 November 2012 ABSTRACT Aims. We present spectroscopic observations of 182 disk galaxies (96 in the cluster and 86 in the field environment) in the region of the Abell 901/902 multiple cluster system, which is located at a redshift of z ∼ 0.165. We estimate dynamical parameters of the four subclusters and analyse the kinematics of spiral galaxies, searching for indications of ram-pressure stripping. Furthermore, we focus on dusty red galaxies as a possible intermediate stage in the transformation of field galaxies to lenticulars when falling into the cluster. Methods. We obtained multi-object slit spectroscopy using the VLT instrument VIMOS. We carried out a redshift analysis, determined velocity dispersions using biweight statistics, and detected possible substructures with the Dressler-Shectman test.
    [Show full text]